Segment for forming tubular structures



Nov. 28, 1939. wH|TE Q I 2.181509 SEGMENT FOR FORMING TUBULAR STRUCTURES Filed July 28, 1938 T 2 Sheets-Sheet l INVENTOR Tho m as L. Whi'l'e Nov. 28, 1939. v T, w rr 2.181509 SEGMENT FOR FORMING TUBULAR STRUCTURES Filed July 28, 1938 2 Sheets-Sheet 2 INVENTOR I Thomas L.'Whi1'e m MJM Patented Nov. 1939 UNITED. STATES PATENT; OFFICE SEGMENT FOR FORMING TUBULAR I STRUCTURES Application July 28, ms. Serial No. 221,309 I 6 Claims. (oi. 01-45) This invention relates to segments such as are employed in the construction of large size culverts, tunnel linings, etc.

Numerous types of segments for forming tubular structures have been proposed heretofore and many of these types have actually been used in various installations. It is the object of this invention to improve generally upon so-called liner segments as previously known and, in particular, to provide a segment having a section modulus which is greater per unit weight of meta1. employed, than those of the types of segments which have been known and used previously. A further object of the invention is the provision of a segment, adapted to be connected end to end to an adjacent segment by a lapped joint characterized by high resistance to circumferential thrust. A further object is to relieve the bolts or other fasteners usually employed go to connect adjacent plates from the shearing stress communicated thereto in the ordinary type of segment by the circumferential forces to which tubular structures are usually subject.

In a preferred form, the invention comprises 25 a plate curved along its longer dimension to the radius of the tubular structure. and having longitudinal corrugations, the troughs and crests of which are cylindrical and connected by conical portions. The segment is deformed adjacent so each end to provide interfitting protuberances and sockets adapted to cooperate with similarly shaped portions of segments disposed end to end thereof in lapped relation for connection as by bolts, rivets or the like. In one form of the 35 invention, the deformation takesthe form of a transverse rib extending the full width of the segment. In a modification, the conical connecting portions of the corrugations are deformed out of their general surfaces adjacent the ends 40 of the segment. In both forms ofthe invention, bolt or rivet holes are formed in the ends of the segment adjacent the aforementioned deformations.

The following detailed description of the in- 45 vention refers to the accompanying drawings illustrating one preferred embodiment and a modification, although it will be understood that the invention may be otherwise embodied within the scope of'my broader claims. In the drawings:

50 Fig. 1 is a partial side elevation of a ring formed by connecting a plurality of the segments of my invention in end to end, lappedrelation;

Fig. 2 is a partial plan view;

so Fig. 8 is a diagrammatic end elevation to reduced scale showing the assembly of a plurality of segments to form a complete ring, successive rings being disposed side by side in the customary manner to build up the complete tubular structure;

Fig. 4 is a sectional view taken substantially 5 along the line IV-IV of Fig. 2;

Fig. 5 is a transverse sectional view through a segment taken along the line VV of Fig. i;

Fig. 6 is a partial plan view showing two segments of a modified form connected end to end in 10 lapped relation.

Fig. '7 is a sectional view taken substantially along the lines VII-'-VII of Fig. 6;

Fig. 8 is a transverse section with a Joint between adjacent segments, substantially along the 15 line VIII--VIII of Fig. 6; and

Figs. 9 and 10 are further sectional views taken along theline IX-IX and X-X-of Fig. 6.

Referring now in detail to the drawings and, for the present, to Figs. 1 through 5, segments II are formed from metalplates of suitable size and thickness and are curved along their length to the radius of the desired finished structure. The segments may conveniently be manufactured from flat stock by a drawing or stamping operation. The edge portions of the segments are bent inwardly to form connection flanges ll, Bolt holes l2 punched therein permit adjacent rings of segments to be secured together side by side by bolts I3. The segments of each ring are disposed end to. end in lapped relation as indicated in Fig. 3 and secured together by bolts it. Other types of fastenerssuch as rivets, may be substituted for the bolts shown if desired.

The segments Ill have corrugations I5 extending longitudinally thereof. The corrugations have troughs l6 and crests H which define portions :of cylindrical surfaces. Between the troughs'and crests extend connecting portions i8 which define conical surfaces.

At both ends of the segments, transverse grooves or ribs I9 are formed. These ribs extend across the cylindrical portions i6 and ll of the corrugations as well as the conicalportions l8 thereof and are spaced a short distance inwardly from the extreme ends of the segments. The ribs I9 at theends of the segments provide protuberances and-recesses which are adapted. to interflt, as best shown in Fig. 4, when the ends of adjacent plates are lapped to the necessaryextent. a 1

Bolt-holes 2| are punched, in the ends of the segments in alinement with the ribs I9 for the reception of the bolts l4. Nuts 22 are welded as at 22' on the outer surface of the segments in alinement with the holes at the end which is to be positioned on the outside at a lapped joint as shown in Fig. 4. Grooved washers 28 on the bolts ll engage the curved protuberances formed by the rib it in the inner segment end and provide flat bearing surfaces for the heads of the bolts ll.

It will be apparent that the inter-locking engagement of the ribs II at the ends of lapped segments provides a substantial resistance to stresses directed circumferentially of the completed structure. This engagement, furthermore, relieves the bolts ll of the shearing stress which would otherwise be communicated to them. The effectiveness of the inter-locking ribs in withstanding circumferential stress is increased by punching the bolt holes along the center lines of the ribs. The joint formed by the ribs and the bolts extending therethrough is characterized not only by high mechanical strength but also a high resistance to the in-fiow of fluids.

The character of the corrugations as best shown in Fig. 5 gives to the segments a higher modulus of elasticity per unit weight than has heretofore been attained with segments having other types of corrugations, e.g., the so-called sinuous corrugations defined by circular arcs which are commonly formed in the stock used for fabricating small culverts. It will be observed that the sectional areas of the portions of the segment on opposite sides of the neutral plane are practically equal, indicating that the material is being used with the maximum of efllciency.

A modified form of the invention, which is similar in general to that already described, is illustrated in Figs. 6 through 10. The form of segment there shown, however, does not have continuous transverse ribs such as indicated at I! in Figs. 2, 4 and 5. Instead, the conical portions I! of the corrugations are deformed out of their normal surface as at 30. As best shown in Fig. 8, the outer edge of the conical portion i8 is deformed outwardly from the conical surface while the inner portion is deformed inwardly thereof. The deformations 30 form interlocking protuberances and sockets such that on lapping the ends of adjacent plates, and securing them together as by bolts ",the interlocking portions of the segments resist circumferential stress and prevent it from being transmitted as shearing stress to the bolts 3 l In addition to the deformations 30, the conical portions ll of the segments are deformed in the opposite direction as indicated at 32. This increases the interlocking of the deformed parts of adjacent segments disposed in lapped end to end relation. It will be noted that deformations 32 are formed on each side of the deformations Ill.

The nuts 33 cooperating with the bolts 3i may be welded to the segments at one end thereof in the same manner as the bolts 22 As shown in Fig. 6, the holes for bolts Ii arepunched in alinement with the deformations Ill.

Fig. 6 illustrates the cutting away of the side flanges II at one end of the segment as at 34 to the depth to which the ends of adjacent segments overlap.

The modified form of segment shown in Figs. 6 through 10 is characterized by all the advantages previously mentioned with reference to the form of segment initially described, which it is unnecessary to repeat. The action of both the ribs I. and the deformations l0 and 32 may be described as a keying action which looks adjacent segments against relative movement longitudinally so long as the interfitting protuberances and sockets are held together by the bolts I4 and ti, thus relieving the bolts of most of the shearing stress to which they would otherwise be subject.

Although I have illustrated and described herein but one preferred embodiment of the invention and a modification, various changes in the details of thesegments illustrated may be made without departing from the spirit of the invention or the scope of the appended claims.

I claim:

1. A liner segment comprising a curved metal plate having corrugations extending along one dimension thereof, a rib extending along the other dimension adjacent each end of the plate and bolt holes through said plate adjacent said ribs whereby the latter withstand thrust longitudinally of plates bolted together with their ribs interlocking.

2. A liner segment comprising a curved metal -plate having corrugations extending along one dimension thereof, said corrugations having troughs and crests defined by cylindrical surfaces and connecting portions extending therebetween defined by conical surfaces, and ribs extending transversely of said corrugations adjacent each end of the plate.

3. A liner segment comprising a curved metal plateshaving corrugations extending along one dimension thereof, said corrugations having troughs and crests defined by cylindrical surfaces and connecting portions extending therebetween defined by conical surfaces, said conecting portions being deformed out of the general plane thereof in one direction adjacent the ends of the plate and in the reverse direction at points spaced inwardly of said first-mentioned deformations, to form protuberances and sockets adapted to interfit on lapping the end of one segment over the end of another.

4. An assembly of liner segments disposed end to end, each comprising a curved metal plate having corrugations extending along one dimension thereof, and a rib extending along the other dimension adjacent each end of the plate, said ribs being adapted to nest with similar ribs on plates disposed in end to end, lapped relation therewith, thereby transmitting both tensile and compressive force across the joints therebetween,

and means for securing the lapped ends of said.

plates together.

5. A joint connecting lapped plates wherein an edge of one plate laps the edge of an adjacent plate, said joint including depressions spaced apart along the lapping edge of said one plate, protuberances similarly spaced along the lapped edge of the adjacent plate, said protuberances nesting in said depressions when the edge of said first-mentioned plate is in lapping relation to jacent plate, said protuberances nesting in said depressions when the edge of said first-mentioned plate is in lapping relation to the edge of said adjacent plate with their corrugations nesting, and means securingthe lapped edges of said plates together.

THOMAS L. WHITE. 

